PurposeTo evaluate the feasibility of using a simplified non-coplanar volumetric modulated arc therapy (NC-VMAT) and investigate its dosimetric advantages compared with intensity modulated radiation therapy (IMRT) and coplanar volumetric modulated arc therapy (C-VMAT) for hippocampal-avoidance whole brain radiation therapy (HA-WBRT).MethodsTen patients with brain metastase (BM) were included for HA-WBRT. Three treatment plans were generated for each case using IMRT, C-VMAT, and NC-VMAT, respectively.ResultsThe dosimetric results of the three techniques complied roughly with the RTOG 0933 criteria. After dose normalization, the V30Gy of whole brain planned target volume (WB-PTV) in all the plans was controlled at 95%. Homogeneity index (HI) of WB-PTV was significantly reduced in NC-VMAT (0.249 ± 0.017) over IMRT (0.265 ± 0.020, p=0.005) and C-VMAT (0.261 ± 0.014, p=0.020). In terms of conformity index (CI), NC-VMAT could provide a value of 0.821 ± 0.010, which was significantly superior to IMRT (0.788 ± 0.019, p<0.001). According to D2% of WB-PTV, NC-VMAT could provide a value of 35.62 ± 0.37Gy, significantly superior to IMRT (36.43 ± 0.65Gy, p<0.001). According to D50% of WB-PTV, NC-VMAT can achieve the lowest value of 33.18 ± 0.29Gy, significantly different from IMRT (33.47 ± 0.43, p=0.034) and C-VMAT (33.58 ± 0.37, p=0.006). Regarding D2%, D98%, and Dmean of hippocampus, NC-VMAT could control them at 15.57 ± 0.18Gy, 8.37 ± 0.26Gy and 11.71 ± 0.48Gy, respectively. D2% and Dmean of hippocampus for NC-VMAT was significantly lower than IMRT (D2%: 16.07 ± 0.29Gy, p=0.001 Dmean: 12.18 ± 0.33Gy, p<0.001) and C-VMAT (D2%: 15.92 ± 0.37Gy, p=0.009 Dmean: 12.21 ± 0.54Gy, p<0.001). For other organs-at-risk (OARs), according to D2% of the right optic nerves and the right lenses, NC-VMAT had the lowest values of 31.86 ± 1.11Gy and 7.15 ± 0.31Gy, respectively, which were statistically different from the other two techniques. For other organs including eyes and optic chiasm, NC-VMAT could achieve the lowest doses, different from IMRT statistically.ConclusionThe dosimetry of the three techniques for HA-WBRT could roughly comply with the proposals from RTOG 0933. After dose normalization (D95%=30Gy), NC-VMAT could significantly improve dose homogeneity and reduce the D50% in the brain. Besides, it can reduce the D2% of the hippocampus, optic nerves, and lens. With this approach, an efficient and straightforward plan was accomplished.

Objective To explore the role of microbiota abnormality in pathogenesis of nasopharyngeal carcinoma.Methods With 5 healthy individuals as the controls and 7 patients diagnosed as nasopharyngeal squamous carcinoma who had not received any treatment as the subjects,polymerase chain reaction-modified gradient gel electrophoresis (PCR-DGGE) gene fingerprint technology was used to observe the differences in the microbiota in nasopharyngeal lavage fluid between the patients and healthy individuals.The total DNA was extracted from the nasopharyngeal lavage fluid.The similarity and diversity of microbiota between the two groups were analysed.Results There were significant differences in the distribution of the microbiota in nasopharyngeal lavage fluid between patients and healthy controls.Compared with the controls,the relative abundances of Streptococcus anginosus and Acinetobacters were significantly higher while that of Streptococcus thermophilus was lower in the patients.Conclusion There is significant difference in the distribution of microbiota in the nasopharyngeal lavage fluid between the patients and healthy controls.This study can provide experimental evidence for the prevention and treatment of nasopharyngeal carcinoma.

<正>朗格汉斯组织细胞增生症(Langerhans cell histiocytosis,LCH)是一种朗格汉斯细胞(Langerhans cell,LC)克隆性增生引起的疾病,病因尚不明确,可能与病毒感染、酶代谢障碍、免疫功能低下或创伤有关[1]。每年发病率为0.002‰～0.005‰,10岁以内儿童常见[2]。本院放疗科收治成人肋骨LCH术后复发患者1例,治疗疗效报告如下。

[Objective] To present a more effective way to determinate the target volume in electron beam irradiation while using three-dimensional treatment planning system.[Methods] Contoured the target volume according to the images from CT simulation,and designed the electron beam irradiation field by using 3DTPS.Calculated the shifting coordinate of irradiation field based on the original coordinate.Installed the applicator with the leaden block of electron beam onto the accelerator.Turned on the lamp field and marked the cross line on the plate.A foam mould which was marked with filed centre and direction should be cutted based on the DR image from TPS.The leaden block would be made on a premise that the cross lines on the plate and the foam were coincident.Evaluated the feasibility of this method by radiotherapy verification.[Results] The offset degree of target centre was less than 2.2 mm,also the maximum deviation is less than 1.7 mm.[Conclusion] The method that coincide the irradiation field centre and the centre from TPS can solve the problem of target area's variation.Also the method can ensure the process of electron irradiation going smoothly.

患者,男性,56岁.2010年5月初无明显诱因出现间歇性头痛,6月3日凌晨4时患者头痛加重伴左侧手指麻木,随后出现四肢抽搐及意识障碍,并不慎跌倒,擦伤右额部,昏迷时间持续5 min,清醒后对当时情况记忆不清.头颅CT示:右侧颞顶枕叶交界区低密度影,边界欠清晰,横径约3.2 cm,局部混杂密度,右侧脑室后角略受压,中线无偏移.

高分级脑胶质瘤(HGG)占原发脑肿瘤的35%～45%~([1]).因其多向周围浸润,手术难以彻底切除,术后放疗是目前的标准治疗.笔者回顾分析2004年9月至2007年7月在本院放疗的39例HGG患者手术和术后放疗疗效,以及影响预后的因素.

Introduce the development method of an utility type irradiational measure board, and apply it to the work of radiotherapy irradiation,thereby get a ture diagraph data of body position error margin, effectively improve the accuracy of body position in the radiotherapy.It is an effective way to strenghthen the radiotherapy quality management and quality control.

故障现象 在没有安装托架和限光筒的情况下,旋转机架,准直器上的Reset按钮红灯被点亮,使机架旋转、床升降等运动被锁住,按Reset按钮不能恢复,若一直按住Reset按钮不放,能够恢复各运动.

目的: 探讨放射治疗网络的构建方法和意义.方法: 将各种仪器设备按用途分成三个子网,各子网分别与网络服务器相连,组成一个星形网络拓扑结构的放疗局域网络系统.结果: 对接受治疗的560例患者进行从病例录入、定位、计划设计和治疗实施的网络化管理,未出现超剂量和错误治疗.结论: 放疗网络的构建使各设备之间完全实现了信息共享,不仅提高了工作效率,而且大大增加了治疗的精确性,是放射治疗临床质量保证和质量控制的有效工具.

本文系统介绍了放疗信息管理系统的组成及功能,提供了一套加强放疗科管理的方法,为医院的科学化和规范化管理指明了思路。